The textile part is intended for the use in composite materials that may also be referred to as composites. Such textile-reinforced composite materials have been basically known.
In conventionally woven textile parts a thread convolution is formed due to the binding of warp threads with weft threads so that, when the textile part is used in a composite material element, a non-ideally drawn out orientation of the threads exists. The textile part that is used for reinforcing the composite material and forms a textile layer thus comprises convoluted threads. The achievable strength of the composite material element is thus not optimal. Therefore, kinks, convolutions or small radii should be avoided if at all possible.
By increasing the distances between the binding locations the number and height of the convolutions in the affected thread can indeed be reduced. This means that larger floats are provided, which also increases the drapability of the textile part. However, with extremely large floats there arises the disadvantage that undesirable shifting of the threads of the textile part can occur when it is being draped and, in particular, when the textile part is being moulded into a three-dimensional composite material body. As a result of this, the thread density may be insufficiently low in some places while it is too high in other places.
Instead of woven fabrics it is also possible to use non-woven layers of reinforcing threads as the textile part. Considering these laid structures, however, it is necessary that the reinforcing threads be fused together by an additional means. Indeed, such non-wovens have the disadvantage that some mechanical laminate properties become worse, e.g., perpendicular to the extension plane of the textile part, namely the sliding properties, the properties of the face of a hole, the impact stress properties or the damage-free mechanical processability of the textile part or the composite material element produced therefrom. Inasmuch as there is no typical woven binding between the threads of the textile part, the mechanical properties perpendicular to the extension plane are frequently not adequate.
Another aspect considering the embodiment and production and processing of a textile part, in particular considering the production of a composite material element, is the drapability during a reshaping process. In doing so, the composite material elements can be heated and mechanically reshaped. In transfer moulding it is also possible to form a so-called preliminary form—also referred to as a preform—from the textile part that has been imparted with the desired shape and to produce a composite material body, for example by the injection of liquid resin under high pressure. When a composite material element is being reshaped or when a textile part is being draped, it is not desirable for the threads or fibers to flow and shift in an uncontrolled manner. Considering this method, a laid structure has the advantage that it is indeed highly drapable, however, considering a non-woven, there is the risk that the means for binding the laid structure are not sufficiently firm and that thus the desired thread density is lost in certain areas. On the other hand, woven structures are less drapable and thus harder to reshape.
Publication U.S. Pat. No. 4,320,160 discloses a textile part for composite material bodies. This textile part comprises a reinforcing system of reinforcing threads placed adjacent each other, said threads being bound to each other by binding threads. The bindings threads used are binding warp threads and binding weft threads bound to each other by simple weft threads, or the binding warp threads are bound with the reinforcing warp threads and the reinforcing weft threads, respectively. This textile part has the disadvantage that, based on the suggested binding types, the thread tension of the binding threads must be low in order to avoid undesirable convolutions of the reinforcing threads. This, in turn, has the result that sufficient resistance to a shifting of the reinforcing threads is not ensured. When the desired resistance to shifting is attained, the thread tension of the binding threads causes a convolution of the reinforcing threads, on the one hand, and there is the risk of the reinforcing threads being bundled due to the high thread tension of the binding thread between the binding locations and of an undesirable structure with very uneven thread density of the reinforcing threads, on the other hand.
Publication DE 20 2005 014 801 U1 also discloses a textile part with a reinforcing system of reinforcing threads and a binding system of binding threads for binding the reinforcing system, whereby this implies the same disadvantages that have been described in conjunction with publication U.S. Pat. No. 4,320,160
Publication 10 2005 022 567 A1 describes a planar textile structure that, in a described exemplary embodiment, uses leno weave as well as linen weave between reinforcing threads. For example, after a prespecified number of linen weave bindings, a leno weave binding may always be provided.
Assuming this, it may be viewed as the object of the present invention to provide a textile part, a composite material element with such a textile part, as well as a production method, wherein good handlability in the course of shaping and reshaping of the textile part and the composite material element, respectively is ensured, on the one hand, and sufficient mechanical stability exists, on the other hand.